Journal articles on the topic 'Flow-ecology relationship'
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1
Yin, Zheng Jie, Jin Chen, and Ji Jun Xu. "Application of Multiple Environmental Flow Methods to Optimize Cascade Dams Operation in the Lower Jinsha River." Advanced Materials Research 955-959 (June 2014): 3057–64. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.3057.
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To mitigate possible negative impacts of cascade dams in the Lower Jinsha River and maintain the natural flow regime of national natural reserve areas of rare and special fishes of the upper Yangtze River, environmental flow (e-flow) demands need to be considered in the cascade dams operation. Due to lack of regular ecological observation data, multiple hydrology-based e-flow methods including Tennant, minimum monthly flow, 7Q10 and Q90 are applied to provide specific e-flow prescripts to guide the reservoir release. A joint operation optimization model is developed for the cascade dams in the Lower Jinsha River for maximal hydropower generation under various e-flow constraints. The economic and ecological performances of cascade dams operation are evaluated by total hydropower outputs and hydrological alteration degree of downstream river individually. The operation results are analyzed and discussed, and some questions on the tradeoff relationship between ecology and hydropower generation, inherent relationship between ecological constrains and hydrological alteration, and rationality criteria of e-flow are further addressed. The conclusions indicate : (1) optimal operation for ecological considerations under e-flow constrains only reduce hydropower outputs slightly, no more than 2.4%; (2) e-flow constrains help lower hydrological alteration induced by hydropower dams, among the four e-flow methodologies Tennant is best in term of ecology; (3) there is a limitation for hydrology-based e-flow methodologies, and it is necessary to stress ecological foundation and ecological relevance for e-flow methodology. The paper will provide technical references for future ecological re-operation of the cascade dams.
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Chen, Ang, Miao Wu, and Michael E. McClain. "Classifying Dams for Environmental Flow Implementation in China." Sustainability 12, no. 1 (December 21, 2019): 107. http://dx.doi.org/10.3390/su12010107.
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The implementation of environmental flows is of the utmost importance for ecosystem protection and restoration in dammed rivers. A key challenge in optimizing dam regulation is the uncertainty of the ecohydrology relationship between flow release and ecological response. In the present paper, we develop a framework of dam classification to organize the categories of the ecohydrology relationship for implementing environmental flows. Dams are classified from three major categories that differ in dam properties, hydrological alteration, and downstream hydrobiological diversities based on the relationship of hydrology and ecology. Finally, 773 dams in China are screened and ranked into four classes involving a great diversity of environmental flow components. A classification of dams that utilizes the implementation of environmental flows is presented. (1) Class 1 includes dams with rare and endangered fish species in the downstream. It is the category with the highest priority for environmental flow releases and regulation, requiring continuous flow and flood pulse components for fish spawning and migration. (2) Class 2 includes dams with significant hydrological alteration in the downstream. It is the category with second priority for environmental flow releases and regulation, requiring natural hydrological regimes simulation or complete flow component recovery for optimizing the flow duration curve and mitigating adverse impacts of dam operation. (3) Class 3 includes dams with a high degree of regulation where there is urgency for environmental flow releases and regulation, requiring that minimum flow is guaranteed by cascade reservoir regulation. (4) Class 4 includes dams with a low degree of regulation where there is less urgency for environmental flow releases and regulation. This classification method is important for future research, including environmental flow release regulation and the effectiveness evaluation of environmental flow adaptive management. It will be useful for guiding the implementation of environmental flows.
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Jacoby, David M. P., Penthai Siriwat, Robin Freeman, and Chris Carbone. "Is the scaling of swim speed in sharks driven by metabolism?" Biology Letters 11, no. 12 (December 2015): 20150781. http://dx.doi.org/10.1098/rsbl.2015.0781.
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The movement rates of sharks are intrinsically linked to foraging ecology, predator–prey dynamics and wider ecosystem functioning in marine systems. During ram ventilation, however, shark movement rates are linked not only to ecological parameters, but also to physiology, as minimum speeds are required to provide sufficient water flow across the gills to maintain metabolism. We develop a geometric model predicting a positive scaling relationship between swim speeds in relation to body size and ultimately shark metabolism, taking into account estimates for the scaling of gill dimensions. Empirical data from 64 studies (26 species) were compiled to test our model while controlling for the influence of phylogenetic similarity between related species. Our model predictions were found to closely resemble the observed relationships from tracked sharks, providing a means to infer mobility in particularly intractable species.
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Lange, Katharina, Colin R. Townsend, and Christoph D. Matthaei. "Inconsistent Relationships of Primary Consumer N Stable Isotope Values to Gradients of Sheep/Beef Farming Intensity and Flow Reduction in Streams." Water 11, no. 11 (October 26, 2019): 2239. http://dx.doi.org/10.3390/w11112239.
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Stable isotope values of primary consumers have been proposed as indicators of human impacts on nitrogen dynamics. Until now, these values have been related only to single-stressor gradients of land-use intensity in stream ecology, whereas potential interactive effects of multiple stressors are unknown. It also remains unknown whether stable isotope values of different primary consumers show similar relationships along gradients of stressor intensities. We sampled three common invertebrate grazers along gradients of sheep/beef farming intensity (0–95% intensively managed exotic pasture) and flow reduction (0–92% streamflow abstracted for irrigation). The δ15N values of the three primary consumers differed substantially along stressor gradients. Deleatidium δ15N values were positively related to farming intensity, showing a saturation curve, whereas Physella snail δ15N values were negatively related to farming intensity and Potamopyrgus snail δ15N values showed no relationship. In addition, Deleatidium stable isotope values responded positively to flow reduction intensity, a previously unstudied variable. An antagonistic multiple-stressor interaction was detected only for the mayfly Deleatidium, which occurred in streams experiencing up to 53% farming intensity. The lack of consistency in the relationships of the most important primary consumer grazers along the studied gradients may reduce their suitability as an indicator of anthropogenic N inputs.
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Chen, Mufeng, Zengchuan Dong, Wenhao Jia, Xiaokuan Ni, and Hongyi Yao. "Multi-Objective Joint Optimal Operation of Reservoir System and Analysis of Objectives Competition Mechanism: A Case Study in the Upper Reach of the Yangtze River." Water 11, no. 12 (December 1, 2019): 2542. http://dx.doi.org/10.3390/w11122542.
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The multi-objective optimal operation and the joint scheduling of giant-scale reservoir systems are of great significance for water resource management; the interactions and mechanisms between the objectives are the key points. Taking the reservoir system composed of 30 reservoirs in the upper reaches of the Yangtze River as the research object, this paper constructs a multi-objective optimal operation model integrating four objectives of power generation, ecology, water supply, and shipping under the constraints of flood control to analyze the inside interaction mechanisms among the objectives. The results are as follows. (1) Compared with single power generation optimization, multi-objective optimization improves the benefits of the system. The total power generation is reduced by only 4.09% at most, but the water supply, ecology, and shipping targets are increased by 98.52%, 35.09%, and 100% at most under different inflow conditions, respectively. (2) The competition between power generation and the other targets is the most obvious; the relationship between water supply and ecology depends on the magnitude of flow required by the control section for both targets, and the restriction effect of the shipping target is limited. (3) Joint operation has greatly increased the overall benefits. Compared with the separate operation of each basin, the benefits of power generation, water supply, ecology, and shipping increased by 5.50%, 45.99%, 98.49%, and 100.00% respectively in the equilibrium scheme. This study provides a widely used method to analyze the multi-objective relationship mechanism, and can be used to guide the actual scheduling rules.
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Tucker, Marlee A., and Tracey L. Rogers. "Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals." Proceedings of the Royal Society B: Biological Sciences 281, no. 1797 (December 22, 2014): 20142103. http://dx.doi.org/10.1098/rspb.2014.2103.
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Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial ( n = 51) and marine ( n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities.
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Newson, M. D., and C. L. Newson. "Geomorphology, ecology and river channel habitat: mesoscale approaches to basin-scale challenges." Progress in Physical Geography: Earth and Environment 24, no. 2 (June 2000): 195–217. http://dx.doi.org/10.1177/030913330002400203.
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The physical component of river channel (instream) habitat is of acknowledged significance, particularly in headwater streams; furthermore, physical habitats have been heavily impacted by human needs for river services: principally flood defence (channel modification) and water resources (flow regulation). Despite the control exercised on physical habitats by fluvial geomorphology (channel shape, bed material size, bedforms and bars) and flow regime (including the varying hydraulics of flow around these forms), their interaction has hitherto lacked a distinctive spatial formulation and biological validation. This article describes the challenges faced by a need (in both theoretical and practical areas) to understand the detail of physical habitat conditions in stream channels. A number of mesoscale approaches are emerging, both from ecology and geomorphology. We outline the field validation of a ‘habitat hydraulics’ approach to the interaction between river discharge and channel form. Qualitative ‘flow types’ are shown to be representative of discrete hydraulic conditions within mesoscale units of the channel bed described as ‘physical biotopes’. The approach is compared with parallel ecological research on ‘mesohabitats’ and ‘functional habitats’. The extent, pattern and discharge-variability of physical biotopes can be surveyed in the field and used as a spatial guide to biological sampling (in this case for benthic invertebrates). Biological patterns (at the scale sampled here) appear to respond first to the river continuum concept’s longitudinal zonation of the channel, but there is a marked secondary signal in statistical analyses from the pattern of biotopes. Given the promise of the physical biotope approach, its logical extension in predictive mode is via the hierarchical concepts shared by freshwater ecologists and geomorphologists; however, there is little agreement on scale terminology, hierarchical principles and, above all, a truly geo-morphological channel classification, based on reaches, into which mesoscale habitat typologies could be fed. Assuming a relationship between biological diversity and that of physical biotopes it should be the aim of river managers, whether intervening in the channel form or its flow regime, to optimize certain parameters of the pattern of biotopes; these parameters should be a focus for future research. Both the rapid survey and proper description of these patterns will benefit from the application of remote-sensing technology, improved instruments for microscale hydraulic studies and a GIS approach based upon the spatial principles of landscape ecology.
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Wang, Hong Tao, Jin Yong Zhao, Gai Ling Wang, and Qing Hong Huangfu. "Significance of Ecohydraulics in Aquatic Ecosystem Protection." Advanced Materials Research 864-867 (December 2013): 2413–17. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.2413.
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Ecohydraulics is an emerging interdisciplinary science and mainstream engineering researching on the interaction relationship between hydrodynamic characteristic and aquatic ecosystem, it integrates biology, geology, hydrology, morphology, ecology, engineering and other disciplines. Based on the collection of literature on ecohydraulics from Web of Science database, the bibliometric analysis on 563 literatures from the year 1991 to 2012 has been conducted, including publication year, author, country, institution, subject, source journal and keyword analysis. Some conclusions have been made that these literatures on ecohydraulics are growing exponentially year by year; these literature involves a lot of authors and forms three research groups which scattered in Britain, the United States and New Zealand, the result clearly shows a positive correlation between the number of published literatures and the length of the research history in this subject; the main institutions of these literature include United States Geological Survey, National Institute of Water and Atmospheric Research, Chinese Academy of Sciences, University of Lyon and University of Birmingham; and the subjects of these literature include environmental sciences & ecology, water resources, marine & freshwater biology, engineering and other subjects; more than 40% of the literature published in journals with the impact factors greater than 2.0. The main research contents are as follow: biological characteristics of aquatic organism, the impact of hydrodynamics on river habitats and aquatic organisms and, the feedback of the organism on flow. Theoretical analysis, system testing, statistical analysis and hybrid analog-digital simulation are primary research techniques and applications of the research concentrate on environmental flow requirement, habitat assessment, eco-engineering design and flow field control.
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von Cramon-Taubadel, Noreen, and Stephen J. Lycett. "Assessing the relative impact of historical divergence and inter-group transmission on cultural patterns: a method from evolutionary ecology." Philosophical Transactions of the Royal Society B: Biological Sciences 373, no. 1743 (February 12, 2018): 20170054. http://dx.doi.org/10.1098/rstb.2017.0054.
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In the study of cultural evolution, observed among-group affinity patterns reflect the effects of processes such as mutation (e.g. innovation and copying error), between-group interaction (culture flow), drift and selection. As in biology, cultural affinity patterns are often spatially correlated, making it difficult to distinguish between the opposing geographically mediated forces of divergence and interaction, which cause groups to become more distinct or similar over time, respectively. Analogous difficulties are faced by evolutionary biologists examining the relationship between biological affinity and geography, particularly at lower taxonomic levels where the potential for gene flow between lineages is greatest. Tree models are generally used to assess the fit between affinity patterns and models of historical divergence. However, factors driving lineage divergence are often spatially mediated, resulting in tree models that are themselves geographically structured. Here, we showcase a simple method drawn from evolutionary ecology for assessing the relative impact of both geographically mediated processes simultaneously. We illustrate the method using global human craniometric diversity and material culture from the northern coast of New Guinea as example case studies. This method can be employed to quantify the relative importance of history (divergence) and geographically mediated between-group interaction (culture flow) in explaining observed cultural affinity patterns. This article is part of the theme issue ‘Bridging cultural gaps: interdisciplinary studies in human cultural evolution’.
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Clark, René D., Matthew L. Aardema, Peter Andolfatto, Paul H. Barber, Akihisa Hattori, Jennifer A. Hoey, Humberto R. Montes, and Malin L. Pinsky. "Genomic signatures of spatially divergent selection at clownfish range margins." Proceedings of the Royal Society B: Biological Sciences 288, no. 1952 (June 9, 2021): 20210407. http://dx.doi.org/10.1098/rspb.2021.0407.
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Understanding how evolutionary forces interact to drive patterns of selection and distribute genetic variation across a species' range is of great interest in ecology and evolution, especially in an era of global change. While theory predicts how and when populations at range margins are likely to undergo local adaptation, empirical evidence testing these models remains sparse. Here, we address this knowledge gap by investigating the relationship between selection, gene flow and genetic drift in the yellowtail clownfish, Amphiprion clarkii, from the core to the northern periphery of the species range. Analyses reveal low genetic diversity at the range edge, gene flow from the core to the edge and genomic signatures of local adaptation at 56 single nucleotide polymorphisms in 25 candidate genes, most of which are significantly correlated with minimum annual sea surface temperature. Several of these candidate genes play a role in functions that are upregulated during cold stress, including protein turnover, metabolism and translation. Our results illustrate how spatially divergent selection spanning the range core to the periphery can occur despite the potential for strong genetic drift at the range edge and moderate gene flow from the core populations.
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Cowdy, Cheryl. "The Visual Poetics of Play: Childhood in Three Canadian Graphic Novels." Global Studies of Childhood 1, no. 4 (January 1, 2011): 291–301. http://dx.doi.org/10.2304/gsch.2011.1.4.291.
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This article explores the ideological work of play as it is represented in three contemporary graphic narratives – Kean Soo's Jellaby and Jellaby: monster in the city, and Mariko & Jillian Tamaki's Skim, analyzing the relationship these texts create between urban spaces and the ‘innovative’ spaces of the panel and page. The author is interested in the various ways the graphic novel can be read as a ‘leisure genre’ (to borrow a term coined by cultural anthropologist Victor Turner) that creates a dynamic, interactive ecology, encouraging protagonists and readers to participate in a ludic, pediarchic poetics of play. The content and the formal properties of these texts posit ‘play’ dynamically in relationship to ‘flow’ as a subject of the texts' critique, but also as an activity occurring in the liminal spaces in and between panels. The novels address readers as clever, sophisticated accomplices in the meaning-making process. Play is represented as subversive of adult authoritarianism and narrative domination, thwarting the co-optation and commodification of play in the cultures of young people.
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Li, Mingqian, Xiujuan Liang, Changlai Xiao, Xuezhu Zhang, Guiyang Li, Hongying Li, and Wenhan Jang. "Evaluation of Reservoir-Induced Hydrological Alterations and Ecological Flow Based on Multi-Indicators." Water 12, no. 7 (July 21, 2020): 2069. http://dx.doi.org/10.3390/w12072069.
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Although they fulfill various needs of human beings, reservoirs also cause hydrological regime variation in the downstream regions, thus affecting ecological diversity. Therefore, studying the reservoir-induced hydrological alterations and ecological effects is of great significance, as it could guide the regulation of the reservoir to protect the river ecology. In this study, taking the Taizi River as an example, the impact of a reservoir on hydrological alteration and ecological diversity was comprehensively evaluated through eco-flow indicators based on the flow duration curve and multiple hydrological indicators. The results reveal that: (1) Ecological indicators can be used to analyze the annual and seasonal changes in the streamflow after the construction of the reservoir. The high-flow values and frequency decrease after the construction of the reservoir, especially in the autumn, while the low-flow component values increase significantly, especially in spring and summer. (2) The main influencing factors of the ecological indicators can be reflected by the relationship with precipitation, as the annual ecosurplus is not significantly affected by the reservoir, while the ecodeficit is greatly affected, and the seasonal ecological indicators (especially in spring and summer) are greatly affected by the reservoir. (3) The indicators of hydrologic alteration (IHA) show significant changes after the construction of the reservoir and are consistent with the changes in the eco-flow indicators; the change in the Shannon index indicates that the ecological diversity reduced after construction of the reservoir. It is controlled by the reservoir, and a new equilibrium state appears. (4) The eco-flow indicators have a good correlation with the 32 IHAs; they can reflect the change information of most IHAs and can avoid statistical redundancy.
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Bell, Katherine L., Chris C. Nice, and Darrin Hulsey. "Population Genomic Evidence Reveals Subtle Patterns of Differentiation in the Trophically Polymorphic Cuatro Ciénegas Cichlid, Herichthys minckleyi." Journal of Heredity 110, no. 3 (January 17, 2019): 361–69. http://dx.doi.org/10.1093/jhered/esz004.
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Abstract In recent decades, an increased understanding of molecular ecology has led to a reinterpretation of the role of gene flow during the evolution of reproductive isolation and biological novelty. For example, even in the face of ongoing gene flow strong selection may maintain divergent polymorphisms, or gene flow may introduce novel biological diversity via hybridization and introgression from a divergent species. Herein, we elucidate the evolutionary history and genomic basis of a trophically polymorphic trait in a species of cichlid fish, Herichthys minckleyi. We explored genetic variation at 3 hierarchical levels; between H. minckleyi (n = 69) and a closely related species Herichthys cyanoguttatus (n = 10), between H. minckleyi individuals from 2 geographic locations, and finally between individuals with alternate morphotypes at both a genome-wide and locus-specific scale. We found limited support for the hypothesis that the H. minckleyi polymorphism is the result of ongoing hybridization between the 2 species. Within H. minckleyi we found evidence of geographic genetic structure, and using traditional population genetic analyses found that individuals of alternate morphotypes within a pool appear to be panmictic. However, when we used a locus-specific approach to examine the relationship between multi-locus genotype, tooth size, and geographic sampling, we found the first evidence for molecular genetic differences between the H. minckleyi morphotypes.
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Geng, Dian Ming, Jin Ke Li, Jia Xiang Liu, and Xiao Lu Song. "System Analysis of Circular Economy Development in Coal Mining Area." Advanced Materials Research 524-527 (May 2012): 2735–40. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2735.
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Coal mining area ecology industrial chain (nets) is an industry networked economic organization based on the mode of circular economy; industries and environment are related through energy flow to form a "nutrition" relationship between the mining industries. Through the optimized analysis of mine area eco-industry, when surplus scale of the active industry unit exceed absorption scale the passive industry unit, passive industry unit scale enlarge and the excess material are disposed outside the industry chain (nets); otherwise, it should reduce the passive industry unit scale or obtain the surplusage from the outside of industry chain (nets); When both of them are equal, the industry units of mining area eco-industrial chain (nets) are in coordination state. Coal mining area circular economy has three practical modes: ecotype coal circular economy unit, ecotype coal circular economy park and ecotype coal circular economy city.
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Johnson, Marc T. J., Cindy M. Prashad, Mélanie Lavoignat, and Hargurdeep S. Saini. "Contrasting the effects of natural selection, genetic drift and gene flow on urban evolution in white clover ( Trifolium repens )." Proceedings of the Royal Society B: Biological Sciences 285, no. 1883 (July 18, 2018): 20181019. http://dx.doi.org/10.1098/rspb.2018.1019.
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Urbanization is a global phenomenon with profound effects on the ecology and evolution of organisms. We examined the relative roles of natural selection, genetic drift and gene flow in influencing the evolution of white clover ( Trifolium repens ), which thrives in urban and rural areas. Trifolium repens exhibits a Mendelian polymorphism for the production of hydrogen cyanide (HCN), a potent antiherbivore defence. We quantified the relative frequency of HCN in 490 populations sampled along urban–rural transects in 20 cities. We also characterized genetic variation within 120 populations in eight cities using 16 microsatellite loci. HCN frequency increased by 0.6% for every kilometre from an urban centre, and the strength of this relationship did not significantly vary between cities. Populations did not exhibit changes in genetic diversity with increasing urbanization, indicating that genetic drift is unlikely to explain urban–rural clines in HCN frequency. Populations frequently exhibited isolation-by-distance and extensive gene flow along most urban–rural transects, with the exception of a single city that exhibited genetic differentiation between urban and rural populations. Our results show that urbanization repeatedly drives parallel evolution of an ecologically important trait across many cities that vary in size, and this evolution is best explained by urban–rural gradients in natural selection.
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Wainwright, Dylan K., Elizabeth A. Karan, and David C. Collar. "Evolutionary patterns of scale morphology in damselfishes (Pomacentridae)." Biological Journal of the Linnean Society 135, no. 1 (December 2, 2021): 138–58. http://dx.doi.org/10.1093/biolinnean/blab140.
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Abstract Fish scales are bony plates embedded in the skin that vary extensively in shape across taxa. Despite a plethora of hypotheses regarding form–function relationships in scales, we know little about the ecological selective factors that shape their diversity. Here we examine evolutionary patterns of scale morphology using novel three-dimensional topography from the surfaces of 59 species of damselfishes, a prominent radiation of coral reef fishes. We find evidence that scale morphology changes with different flow environments, such that species that spend more time in open-water habitats have smoother scales. We also show that other aspects of ecology lead to highly derived scales. For example, anemonefishes show an evolutionary transition to smaller scales and smaller ctenii (scale spines). Moreover, changes in body shape, which may reflect ecological differentiation, are related to scale shape but not surface properties. We also demonstrate weak evolutionary integration among multiple aspects of scale morphology; however, scale size and shape are related, and scale morphology is correlated between different body regions. Finally, we also identify a relationship between aspects of lateral line pore morphology, such that the number of lateral line pores per scale and the size of those pores are inversely related. Overall, our study provides insights into the multidimensionality of scale evolution and improves our understanding of some of the factors that can give rise to the diversity of scales seen across fishes.
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Meynecke, J. O. "Coastal habitat connectivity ? implications for declared fish habitat networks in Queensland, Australia." Pacific Conservation Biology 15, no. 2 (2009): 96. http://dx.doi.org/10.1071/pc090096.
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Estuaries are widely recognized as key habitats supporting nearshore secondary production and catch of commercial fisheries. In Queensland, some of these coastal marine habitats are protected by the declared fish habitat programme run by the Department of Primary Industries and Fisheries. Expected environmental changes for Australian estuarine systems include reduced freshwater flow, increased sedimentation and with them, a loss of connectivity. At present, the relationship between the protected declared fish habitat and habitat connectivity remains unknown. By comparing long term coastal fish catch data with geomorphic characteristics of coastal habitats structural connectivity was previously identified as a potential driver of commercial fish catch in Queensland. An ecology landscape approach was used for this study to identify potential fish habitat hotspots along the coastline of Queensland thus allowing better defined networks of declared fish habitats. A comparison between this approach and the current declared fish habitats demonstrated potential deficits and provided important insights for fisheries management. Declared fish habitats should be placed in coastal habitats with high structural connectivity to ensure sustainability of fisheries in light of environmental changes.
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Halliday-Isaac, Akacia K., Jennilee B. Robinson, Edwin Cruz-Rivera, Andrew G. Campbell, and Paul C. Sikkel. "Environmental Correlates of Prevalence of an Intraerythrocytic Apicomplexan Infecting Caribbean Damselfish." Parasitologia 1, no. 2 (May 2, 2021): 69–82. http://dx.doi.org/10.3390/parasitologia1020009.
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Parasites are an integral part of coral reef ecosystems due to their influences on population dynamics, biodiversity, community structure, and food web connectivity. The Phylum Apicomplexa contains ubiquitous animal associates including the causative agents of globally important human diseases such as malaria and cryptosporidiosis. Despite their ubiquity, little is known about the biology, ecology, or distribution of these microorganisms in natural animal populations. In the US Virgin Islands, the dusky damselfish (Stegastes adustus) had a high but variable incidence of a Haemohormidium-like blood apicomplexan among 30 sites sampled. Microscopic analyses of blood smears allowed us to group these fish as infected, having low intensity infections, or uninfected. Regression analyses detected no significant differences in the condition indices (expressed as length–mass ratio). However, infection was clearly associated with potentially extremely high leukocyte counts among infected S. adustus that were not seen in uninfected fish. These results suggested the potential for some impact on the host. Linear mixed effects models indicated that S. adustus population density and meridional flow velocity were the main predictors of apicomplexan prevalence, with presence of other Stegastes species, population distance from watershed, zonal flow velocity, the complexity of the surrounding habitat, and season not showing any significant relationship with fish infection.
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Eastman, Michael, Simon Parry, Catherine Sefton, Juhyun Park, and Judy England. "Reconstructing Spatiotemporal Dynamics in Hydrological State Along Intermittent Rivers." Water 13, no. 4 (February 14, 2021): 493. http://dx.doi.org/10.3390/w13040493.
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Despite the impact of flow cessation on aquatic ecology, the hydrology of intermittent rivers has been largely overlooked. This has resulted in a lack of monitoring projects, and consequently, datasets spanning a period of sufficient duration to characterise both hydrological extremes. This report documents an investigation into the potential for statistical modelling to simulate the spatiotemporal dynamics of flowing, ponded and dry hydrological states in an internationally rare hydrological state dataset. The models presented predict unrecorded hydrological state data with performance metrics exceeding 95%, providing insights into the relationship between ponding prevalence and the performance of statistical simulation of this ecologically important intermediate state between drying and flowing conditions. This work demonstrates the potential for hydrological intermittence to be simulated in areas where hydrological state data are often sparse, providing opportunities for quality control and data infilling. This further understanding of the processes driving intermittence will inform future water resource assessments and the influence of climate change on hydrological intermittence.
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Baxter, Colden V., and F. Richard Hauer. "Geomorphology, hyporheic exchange, and selection of spawning habitat by bull trout (Salvelinus confluentus)." Canadian Journal of Fisheries and Aquatic Sciences 57, no. 7 (July 1, 2000): 1470–81. http://dx.doi.org/10.1139/f00-056.
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The distribution and abundance of bull trout (Salvelinus confluentus) spawning were affected by geomorphology and hyporheic groundwater - stream water exchange across multiple spatial scales in streams of the Swan River basin, northwestern Montana. Among spawning tributary streams, the abundance of bull trout redds increased with increased area of alluvial valley segments that were longitudinally confined by geomorphic knickpoints. Among all valley segment types, bull trout redds were primarily found in these bounded alluvial valley segments, which possessed complex patterns of hyporheic exchange and extensive upwelling zones. Bull trout used stream reaches for spawning that were strongly influenced by upwelling. However, within these selected reaches, bull trout redds were primarily located in transitional bedforms that possessed strong localized downwelling and high intragravel flow rates. The changing relationship of spawning habitat selection, in which bull trout selected upwelling zones at one spatial scale and downwelling zones at another spatial scale, emphasizes the importance of considering multiple spatial scales within a hierarchical geomorphic context when considering the ecology of this species or plans for bull trout conservation and restoration.
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Hough, Ian, Helen Moggridge, Philip Warren, and James Shucksmith. "Regional flow–ecology relationships in small, temperate rivers." Water and Environment Journal 36, no. 1 (October 19, 2021): 142–60. http://dx.doi.org/10.1111/wej.12757.
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Stewart-Koster, Ben, Julian D. Olden, and Keith B. Gido. "Quantifying flow–ecology relationships with functional linear models." Hydrological Sciences Journal 59, no. 3-4 (April 3, 2014): 629–44. http://dx.doi.org/10.1080/02626667.2013.860231.
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Zerkani, S., E. H. Abba, H. Zerkan, T. Zair, and N.-E. Zine. "The impact of the precipitation on the vegetation and ecological quality in the River of Oued Guigou, Morocco." IOP Conference Series: Earth and Environmental Science 1090, no. 1 (October 1, 2022): 012036. http://dx.doi.org/10.1088/1755-1315/1090/1/012036.
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Abstract Understanding the impact of climate change on vegetation is essential to manage a new adaptation strategy and preserve the ecology impacted by the flow of suspended matter towards the watercourse. The main purposeof the present article is to study the relationship between the normalized difference vegetation index (NDVI) and the precipitation (P), in the Guigou basin, in the Middle Atlas of Morocco. The analysis of the relationship between NDVI and P was carried out in four phases using GIS and remote sensing tools. The NDVI was derived from Landsat TM 5 (1990), LANDSAT ETM + 7 (2000), LANDSAT TM 5 (2010), and LANDSAT OLI 8 (2020). The data on precipitation were homogenized on 2 monitoring stations of AitKabbach and Aitaissa, from 1990 to 2020, using the regional vector method and the variability. The response of vegetation to climatic parameters was represented using zonal statistics. The results show a decrease in annual precipitation during the period (1990-2020) with an increase in the year 2020. In the annual scale, linear regression reported a positive relationship between NDVI and precipitation. Thus, during the study period, the vegetation growth decreased by approximately 90%, between the years 2000 and 2010, in response to the observed climatic variation. The growth of vegetation is affected by climatic variability, in particular the precipitation. Consequently, the pedo-climatic context, favorable to erosive action and runoff, generates the transfer of eroded particles responsible for the clogging of spawning grounds, where salmonid eggs are deposited, in the Guigou wadi.
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Majó-Vázquez, Sílvia, Ana S. Cardenal, Oleguer Segarra, and Pol Colomer De Simón. "Media Roles in the Online News Domain: Authorities and Emergent Audience Brokers." Media and Communication 8, no. 2 (April 16, 2020): 98–111. http://dx.doi.org/10.17645/mac.v8i2.2741.
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This article empirically tests the role of legacy and digital-born news media, mapping the patterns of audience navigation across news sources and the relationship between news providers. We borrow tools from network science to bring evidence that suggest legacy news media retain control of the most central positions in the online news domain. Great progress has been made in discussing theoretically the impact of the Internet on the news media ecology. Less research attention, however, has been given to empirically testing changes in the role of legacy media and the rising prominence of digital-born outlets. To fill this gap, in this study we use the hyperlink-induced topic search algorithm, which identifies authorities by means of a hyperlink network, to show that legacy media are still the most authoritative sources in the media ecology. To further substantiate their dominant role, we also examine the structural position of news providers in the audience network. We gather navigation data from a panel of 30,000 people and use it to reproduce the network of patterns of news consumption. While legacy news media retain control of the brokerage positions for the general population, our analysis—focused on patterns of young news consumers—reveals that new digital outlets also occupy relevant positions to control the audience flow. The results of this study have substantive implications for our understanding of news organizations’ roles and how they attain authority in the digital age.
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Bruckerhoff, Lindsey A., Douglas R. Leasure, and Daniel D. Magoulick. "Flow–ecology relationships are spatially structured and differ among flow regimes." Journal of Applied Ecology 56, no. 2 (November 17, 2018): 398–412. http://dx.doi.org/10.1111/1365-2664.13297.
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Zhao, Qing Jian, and Zuo Min Wen. "Complex Social-Ecological Systems Network：New Perspective on the Sustainability." Advanced Materials Research 361-363 (October 2011): 1467–71. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.1467.
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The complex social-ecological systems network is an integrative platform of ecology, economy, management and complex networks which providing a new perspective on the comprehensive management of ecological and socio economical processes. Through research of the structures, functions and processes, one four-dimensional conceptual model of the complex social-ecological system for sustainable development was set up. The complex social-ecological systems comprise of natural subsystem, social subsystem, economic subsystem and integrative decision subsystem. The complex social-ecological systems network was defined as one six-element tuple which denotes the comprehensive spatial structure with different kinds of nodes of ecosystem, social system and economic system. The complex social-ecological systems network has some important characteristics including hierarchies, power-low, vulnerabilities, resilience, dynamics, co-evolution of flow and structure, et al. At last, based on the Multimedia Environment Pollutant Assessment System (MEPAS) of US EPA, the relationship between POPs (Persistent Organic Pollutants) exposure and lifetime fatal cancer risk was studied, and comprehensive risk network of the Taihu basin water pollution and human body health was established.
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Dell'Aria, Annie. "From Vertical Roll to .MOV File." Afterimage 47, no. 3 (September 1, 2020): 22–42. http://dx.doi.org/10.1525/aft.2020.473004.
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In this article, I examine artworks from two periods in the history of media art—the 1970s and the 2010s—to demonstrate how changes in our haptic relationship to screen media shift the site of criticality in contemporary media art from disruption of electronic feedback toward an intensification and embrace of image flows that actively seek the viewer's touch and gesture. I situate video art within the shifting concept of flow in everyday media consumption, reading video art practices within a larger matrix of bodily and cultural engagement with screens. I locate touch and gesture as both themes in the content of single-channel works and components of the structure of video installation. Artists discussed include Camille Henrot, Joan Jonas, Rafael Lozano-Hemmer, Bruce Nauman, and Hito Steyerl. My analysis bridges media theory and art history with close readings of salient works of art, connecting the structure of artworks employing haptic input to shifts in the broader media ecology and the dynamic interplay of touch, image, and power under our fingertips.
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Zhao, C. S., T. L. Pan, S. T. Yang, Y. Sun, Y. Zhang, Y. R. Ge, B. E. Dong, Z. S. Zhang, and H. M. Zhang. "Quantifying the response of aquatic biodiversity to variations in river hydrology and water quality in a healthy water ecology pilot city, China." Marine and Freshwater Research 70, no. 5 (2019): 670. http://dx.doi.org/10.1071/mf18385.
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Prediction and assessment of the effects of habitat change on aquatic biodiversity remain a hot issue globally. This paper developed a practical methodology based on ecosystem models to comprehensively assess the effects of habitat changes on aquatic biodiversity. The partial least-squares (PLS) method was used to analyse the key hydrological and water quality factors influencing riverine aquatic organisms. The biomass of aquatic organisms under undisturbed conditions was simulated using the food web model Ecosim. Based on the relationship between habitat factors variation and biodiversity variation, a multidimensional river hydrology–water quality–biodiversity response model was established. Application and testing of the methodologies in the first water ecology pilot city in China, namely Jinan City, showed that four water quality factors (total phosphorus, total nitrogen, ammonia nitrogen and dissolved oxygen) significantly affected aquatic biodiversity. For hydrological factors, water depth had a strong effect on fish diversity, whereas flow velocity largely affected fish and algal diversity. The application suggested that response model was practical in modelling the effects of habitat variation on biodiversity. It is anticipated that this model will help assess the effects of changes due to climate- and human-induced stress on aquatic ecosystems and provide a scientific basis for river management decisions.
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Makbul, R., N. Desi, and Sudirman. "Reduction of Gray Water and Run-off in a Residential Environment with Rain Garden Model (Case Study “Settlements in Makassar City”)." IOP Conference Series: Earth and Environmental Science 921, no. 1 (November 1, 2021): 012021. http://dx.doi.org/10.1088/1755-1315/921/1/012021.
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Abstract Residential neighborhoods produce wastewater originating from soapy water, oil, and similar wastes which are included in the gray water category, as well as rainwater runoff from tiles and those that fall in the house, so the best way to consider is to install a water treatment system. integrated waste. The purpose of this study is to identify a Rain Garden model that is suitable for application in the residential areas of Makassar City. The method used is by identifying the suitability of the Rain Garden land, calculating the dimensions, and making the right Rain Garden model. From the results of the study it was concluded that the Rain Garden model for the reduction of gray water and rainwater runoff in the Makassar City residential environment was designed to have three cropping variations. Time to fill RG with the design of the design of Gray Water discharge reservoir and runoff discharge based on water loss in the residential environment. With a flow rate of V = 0.3 m3 / s, the depth of flow Y = l.2 m. Based on the relationship between the width and depth of flow at the best hydraulic section in rectangular shape, the channel bottom is B = 0.8 m, guard height (F) 30% Y=0.36 m. The effectiveness of household waste treatment and rainwater runoff using this Rain Garden model, for BOD = 102.8 mg / L (inlet) to 8.4 mg / L (outlet). The highest TSS value was 79 mg / L (inlet) to 8.3 mg / L (outlet). The highest detergent value was 59.84 mg / L (inlet) and showed the yield after processing was 1.25 mg / L (outlet). Treatment of gray water and rainwater runoff in residential environments is to reduce the volume of liquid waste that enters the city drainage system and create a sustainable urban sanitation ecology.
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Scholl, Cynthia F., Chris C. Nice, James A. Fordyce, Zachariah Gompert, and Matthew L. Forister. "Larval Performance in the Context of Ecological Diversification and Speciation inLycaeidesButterflies." International Journal of Ecology 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/242154.
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The role of ecology in diversification has been widely investigated, though few groups have been studied in enough detail to allow comparisons of different ecological traits that potentially contribute to reproductive isolation. We investigated larval performance within a species complex ofLycaeidesbutterflies. Caterpillars from seven populations were reared on five host plants, asking if host-specific, adaptive larval traits exist. We found large differences in performance across plants and fewer differences among populations. The patterns of performance are complex and suggest both conserved traits (i.e., plant effects across populations) and more recent dynamics of local adaptation, in particular forL. melissathat has colonized an exotic host. We did not find a relationship between oviposition preference and larval performance, suggesting that preference did not evolve to match performance. Finally, we put larval performance within the context of several other traits that might contribute to ecologically based reproductive isolation in theLycaeidescomplex. This larger context, involving multiple ecological and behavioral traits, highlights the complexity of ecological diversification and emphasizes the need for detailed studies on the strength of putative barriers to gene flow in order to fully understand the process of ecological speciation.
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Mulholland, M. R. "The fate of new production from N<sub>2</sub> fixation." Biogeosciences Discussions 3, no. 4 (July 19, 2006): 1049–80. http://dx.doi.org/10.5194/bgd-3-1049-2006.
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Abstract. While we now know that marine N2 fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this production, despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does new production from N2 fixation fuel autotrophic or heterotrophic growth, facilitate carbon (C) export from the euphotic zone, or contribute primarily to microbial productivity and respiration in the euphotic zone? For Trichodesmium, the diazotroph we know the most about, the transfer of recently fixed N2 (and C) appears to be primarily through dissolved pools. The release of N appears to vary among and within populations and, probably as a result of the changing physiological state of cells and populations. The net result of trophic transfers appears to depend on the complexity of the colonizing community and co-occurring organisms. In order to understand the impact of diazotrophy on carbon flow and export in marine systems, we need a better assessment of the trophic flow of elements in Trichodesmium communities dominated by different species, various free and colonial morphologies, and in various defined physiological states. Nitrogen and carbon fixation rates themselves vary by orders of magnitude within and among studies highlighting the difficulty in extrapolating global rates of N2 fixation from direct measurements. Because the stoichiometry of N2 and C fixation does not appear to be in balance with the stoichiometry of particles, and the relationship between C and N2 fixation rates is also variable, it is equally difficult to derive global rates of one from the other. A better understanding of the physiology and physiological ecology of Trichodesmium and other marine diazotrophs is necessary to understand and predict the effects of increased or decreased diazotrophy in the context of the carbon cycle and global change.
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Bower, Luke M., Brandon K. Peoples, Michele C. Eddy, and Mark C. Scott. "Quantifying flow–ecology relationships across flow regime class and ecoregions in South Carolina." Science of The Total Environment 802 (January 2022): 149721. http://dx.doi.org/10.1016/j.scitotenv.2021.149721.
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Aspin, Thomas, Andy House, Alex Martin, and James White. "Reservoir trophic state confounds flow-ecology relationships in regulated streams." Science of The Total Environment 748 (December 2020): 141304. http://dx.doi.org/10.1016/j.scitotenv.2020.141304.
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Davies, Peter M., Robert J. Naiman, Danielle M. Warfe, Neil E. Pettit, Angela H. Arthington, and Stuart E. Bunn. "Flow–ecology relationships: closing the loop on effective environmental flows." Marine and Freshwater Research 65, no. 2 (2014): 133. http://dx.doi.org/10.1071/mf13110.
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Providing flows for biota and environmental processes is a challenging water management issue. For society the ability and willingness to allocate water to sustain the environment is increasingly competitive due to escalating demand and as a consequence of climate change. In response, an array of environmental flow (E-flow) methods have developed. Our view is that few E-flows have been implemented and even fewer evaluated in a research and management context. Much of our science effort in E-flows has been directed primarily at method development, with less attention being given to monitoring, evaluation and subsequent revision of E-flow strategies. Our objectives are to highlight the lack of connection between current trends in E-flow literature and theory with assessment of the efficacy and practical application of these methods. Specifically, effective E-flows need to be explicit about flow-ecology relationships to adequately determine the amount and timing of water required. We briefly outline the historical development of E-flows and discuss how serial development of methods and techniques has restricted implementation, evaluation and revision. We highlight areas where methods are lacking, such as incorporation of data on flow-ecology relationships into operational use of E-flow methods. We suggest four initial steps that will improve the applicability, implementation and ultimate success of E-flows.
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Wheeler, Kit, Seth J. Wenger, and Mary C. Freeman. "States and rates: Complementary approaches to developing flow-ecology relationships." Freshwater Biology 63, no. 8 (September 10, 2017): 906–16. http://dx.doi.org/10.1111/fwb.13001.
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Dupuis, Julian R., Kevin A. Judge, Bryan M. T. Brunet, Shawna Ohlmann Chan, and Felix A. H. Sperling. "Does hunger lead to hybridization in a genus of sexually cannibalistic insects (Orthoptera: Prophalangopsidae)?" Biological Journal of the Linnean Society 131, no. 2 (August 18, 2020): 434–48. http://dx.doi.org/10.1093/biolinnean/blaa094.
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Abstract Allochronic isolation can be a strong mechanism for reproductive isolation and speciation. However, imperfect allochrony and the expression of phenological plasticity can erode temporal barriers to gene flow and result in hybridization between divergent lineages. Here, we combine behavioural ecology and genomics to investigate this scenario in two closely related species of grigs in the genus Cyphoderris. These species exhibit a unique mating system whereby females feed on the fleshy hind wings of the male during copulation, and copulation with conspecific males is more likely in food-restricted females than in well-fed females. In western Canada, Cyphoderris buckelli and Cyphoderris monstrosa are sympatric but largely allochronically separated, with C. buckelli breeding earlier. However, their breeding seasons can overlap, leading to potential for older C. buckelli females to mate with young C. monstrosa males to obtain resources via sexual cannibalism. We used behavioural assays to test whether female feeding status affects the propensity for interspecific mating between C. buckelli females and C. monstrosa males. We then tested for hybridization and gene exchange in wild populations of both species, using morphology, mitochondrial DNA and genome-wide nuclear markers. We found that interspecific courtship and mating can occur, but the relationship between food restriction and increased propensity for hybridization was not significant. Although we observed intraspecific population genetic structure in both species, we found no signatures of hybridization in the morphological or genetic datasets, which suggests that postmating reproductive barriers might be preventing successful hybridization in the wild.
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Lehnhoff, Erik A., Fabian D. Menalled, and Lisa J. Rew. "Tamarisk (Tamarixspp.) Establishment in its Most Northern Range." Invasive Plant Science and Management 4, no. 1 (March 2011): 58–65. http://dx.doi.org/10.1614/ipsm-d-10-00036.1.
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AbstractTamarisk, a shrub or small tree native to Eurasia, was introduced to North America in the early 1800s and is now naturalized throughout many riparian areas of the southwestern United States, where extensive research has been conducted. It is a more recent invader to the northern Great Plains, and fewer studies have been conducted on tamarisk ecology and management in this area. The objectives of this research were to investigate the overwintering potential of tamarisk seeds in Montana and the relationship between hydrologic conditions and historic tamarisk establishment. Emergence of seedlings from seeds stored for different time periods at a range of temperatures was evaluated in a greenhouse study. Emergence rates declined after a 7-d storage period, but storage time had no effect on subsequent emergence rates, and seeds stored at −14 C and 5 C had greater emergence rates than those stored at 20 C and 35 C. Patterns in tamarisk establishment were assessed through age and hydrologic data collected from a reservoir (Fort Peck), a regulated river (Bighorn), and an unregulated river (Yellowstone) in Montana. These data indicated that tamarisk establishment at the reservoir was closely related to historic water levels, whereas establishment on rivers was not related to flow. However, data from the rivers indicated that recruitment differed between regulated and unregulated rivers, with the regulated river having less recruitment after the period of initial colonization than the unregulated river. Our results show that tamarisk seeds have the ability to overwinter in Montana and can establish under a range of flow conditions, indicating potential recolonization of sites after tamarisk removal.
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PLANES, S., R. GALZIN, A. GARCIA RUBIES, R. GOÑI, J. G. HARMELIN, L. LE DIRÉACH, P. LENFANT, and A. QUETGLAS. "Effects of marine protected areas on recruitment processes with special reference to Mediterranean littoral ecosystems." Environmental Conservation 27, no. 2 (June 2000): 126–43. http://dx.doi.org/10.1017/s0376892900000175.
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Although site-attached fish can be expected to increase in abundance in marine protected areas (MPAs), there is little known about recruitment effects. The present work reviews concepts and field evidence for enhancement of recruitment of species in MPAs, focusing geographically on the Mediterranean littoral because of its long history of intensive fishery exploitation, but drawing on evidence from studies on recruitment processes in general on MPAs both in the Mediterranean and elsewhere. We considered recruitment as the process of a fish being added to the local population. The general questions of interest are whether the increase in biomass of species protected in MPAs has an effect on recruitment in the MPAs or in neighbouring areas, and, on competition and predation effects on new recruits. A flow diagram of the effects of MPA status on recruitment is developed and employed to identify the relevant processes. The diagram incorporates three levels of factors: (1) characteristics of MPAs (location, size, habitat type, oceanography and level of protection); (2) life stages of species protected in MPAs relevant to recruitment (eggs, larvae, settlers and juveniles); and (3) fundamental processes of dispersal/movement, predation and competition. From this conceptual diagram, the following main components of the recruitment process were identified and used to structure the review: (1) relationship between the ecology of pelagic stages and the design, location and oceanographic regime of MPAs; (2) effects of protection in MPAs from fishery exploitation of nursery habitats on settlement success; and (3) effects of protection on survival of settlers and juveniles from competition and predation. We found an exceptionally low number of studies specifically addressing recruitment processes in MPAs. This was particularly the case in what concerns the relationship between larval ecology and the characteristics and oceanographic regime of MPAs. The effectiveness of MPAs in promoting recruitment mainly depends on the locations and on sizes of the MPAs in relation to the reproductive biology and larval ecology of the species concerned. The locations and sizes of MPAs in turn depend on MPA objectives, whether the purpose is to protect entire life cycles, the juveniles, or to increase egg production and larval export. The assessment of the relationship between the protection of nursery habitats and settlement success indicates that the magnitude of the effects of protection depends on whether the recruitment of the species involved is restricted to a narrowly-defined set of environmental conditions or, on the contrary, can occur in diverse environments, including areas beyond the influence of the MPAs. Thus, the locations of MPAs determine the habitats which are protected and, consequently, the species, the settlement of which will be favoured. For Mediterranean shallow-water species, the near-shore zone encompasses most of the essential nursery habitats for protection. Recruitment studies conducted in MPAs in the north-western Mediterranean have showed no differences in survival of newly-settled littoral fish between MPAs and the areas outside of them. Conversely, for older recruits, mortality was found to be higher inside MPAs, probably due to the increased abundance and size of large predators. This study highlights the almost total absence of studies addressing even the most elementary questions of recruitment in the specific context of MPAs.
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Cote, J., J. Clobert, T. Brodin, S. Fogarty, and A. Sih. "Personality-dependent dispersal: characterization, ontogeny and consequences for spatially structured populations." Philosophical Transactions of the Royal Society B: Biological Sciences 365, no. 1560 (December 27, 2010): 4065–76. http://dx.doi.org/10.1098/rstb.2010.0176.
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Dispersal is one of the most fundamental components of ecology, and affects processes as diverse as population growth, metapopulation dynamics, gene flow and adaptation. Although the act of moving from one habitat to another entails major costs to the disperser, empirical and theoretical studies suggest that these costs can be reduced by having morphological, physiological or behavioural specializations for dispersal. A few recent studies on different systems showed that individuals exhibit personality-dependent dispersal, meaning that dispersal tendency is associated with boldness, sociability or aggressiveness. Indeed, in several species, dispersers not only develop behavioural differences at the onset of dispersal, but display these behavioural characteristics through their life cycle. While personality-dependent dispersal has been demonstrated in only a few species, we believe that it is a widespread phenomenon with important ecological consequences. Here, we review the evidence for behavioural differences between dispersers and residents, to what extent they constitute personalities. We also examine how a link between personality traits and dispersal behaviours can be produced and how personality-dependent dispersal affects the dynamics of metapopulations and biological invasions. Finally, we suggest future research directions for population biologists, behavioural ecologists and conservation biologists such as how the direction and the strength of the relationship between personality traits and dispersal vary with ecological contexts.
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Connors, V. A., and B. B. Nickol. "Effects of Plagiorhynchus cylindraceus (Acanthocephala) on the energy metabolism of adult starlings, sturnus vulgaris." Parasitology 103, no. 3 (December 1991): 395–402. http://dx.doi.org/10.1017/s0031182000059916.
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Although the relationship between intestinal parasitism, the ingestion and use of energy, and host survival is expected, little work has been done to outline the effect of such organisms upon their host's nutritional requirements in an ecological context. This study is the first to demonstrate that an intestinal helminth previously reported to be of little or no histopathological consequence, Plagiorhynchus cylindraceus, has a significant detrimental impact upon the flow of food energy through a definitive host, the European starling, Sturnus vulgaris. Within both male and female adult European starlings reductions in standard metabolic rates occurred as the result of initial infection, indicating that the host's basal metabolism/thermal regulatory abilities were altered. Moreover, initially infected male starlings, but not females, had an increased consumption and excretion of energy and maintained lower average daily body weights versus controls when temperature stressed. These results appear to be due to either a parasite-mediated alteration in host activity and/or to the disruption of host-digestive abilities. Additionally, these data indicate that, overall, male and female S. vulgaris respond differently to infection and that intestinal helminths normally thought to be of little or no pathological consequence to the host are factors that should be addressed in future studies regarding animal energetics, ecology, and behaviour.
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Werner, Hans U. "MetaSon #5 Skruv Stockholm: turning schizophonic sound into audiovirtual image." Organised Sound 7, no. 1 (April 2002): 73–78. http://dx.doi.org/10.1017/s1355771802001115.
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Schizophonic soundscapes in Murray Schafer's critical acoustic ecology mean a split between listening and seeing, between space and place, between audience and communicator. His idea of a gap between senses is based on electronic media like radio and telephone, but it gains new actuality in modern (multimedia) times. The new technology and its users have too experimented with the creative inversion of schizophony in sound and vision. Film sound design and film music combine sound in and out of context, composition works with contrapunctual audiovisions; video art and sound art, as in the work of Robert Cahen, combine and mix genres of all kinds and senses. MetaSon #5 Skruv Stockholm is an audiovisual soundwalk, based on soundscape recordings in Sweden in the 1970s and 1990s, combined with associative pictures and designs, each in its own rhythms and times. It consists less of the common meaning both share, being more dependent on the fluidity and dynamic of the relationship between the elements. Sound and image create an intermedium, intermodal space neither of which could project alone. From moment to moment, schizophonic montage and idea invert into a fresh, maybe evocative look at the way we perceive, where the audio flow transforms stable pictures into liquid forms, where image follows sound and is treated like sound.
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Gardner, Andrew. "The New Calculus of Bedouin Pastoralism in the Kingdom of Saudi Arabia." Human Organization 62, no. 3 (September 1, 2003): 267–76. http://dx.doi.org/10.17730/humo.62.3.b07e62nwby3mhbew.
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Recent debates have challenged the very foundation of political ecology. One important critique, stemming from the work of Vayda and his associates, promotes a problem-specific, ecological, and positivistic approach to the analysis of the causes of environmental change. Their focus on the “event,” however, is seemingly at odds with earlier concerns with process. Utilizing a case study of the Bedouin people in Saudi Arabia, I argue that the key ecological events upon which this research focuses, the Kuwaiti oil fires and the ongoing process of desertification, provide poor isolates of the human-environment relationship. If we accept the Kuwaiti oil fires as an environmental event, or better, as a point of departure for working backward in time and outward in space, it becomes evident that these events are best comprehended as nodes in a complex web of determination, or nodes in a web of interlinked processes. It is a web that reaches outward to the ebb and flow of the global economy, one that remains inseparable from the nuances of national politics and policy, one that reaches inward to the core cultural values of Bedouin society, and one that reaches backward in time to a series of historic conjunctures and processes.
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Horne, Avril C., Rory Nathan, N. LeRoy Poff, Nick R. Bond, J. Angus Webb, Jun Wang, and Andrew John. "Modeling Flow-Ecology Responses in the Anthropocene: Challenges for Sustainable Riverine Management." BioScience 69, no. 10 (September 4, 2019): 789–99. http://dx.doi.org/10.1093/biosci/biz087.
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Abstract Climate change will increase water stress in many regions placing greater pressures on rivers to meet human and ecological water needs. Managing rivers experiencing water stress requires a fundamental understanding of how ecosystem processes and functions respond to natural and anthropogenic drivers of flow variability and change. The field of environmental flows meets this need by defining “flow-ecology” relationships—mathematical models linking ecological characteristics and dynamics to the underlying flow regime. However, because these relationships are most often based on historical hydrologic regimes, they implicitly assume climatic stationarity. A fundamental challenge in the Anthropocene is how to model flow-ecology relationships such that the effects of nonstationarity can be captured. In the present article, we introduce a novel approach that addresses these shortcomings and show its utility through a series of conceptual and empirical examples. The framework incorporates ecological dynamics and uncertain future hydrologic conditions, as well as nonstationarity itself, thereby providing a viable framework for modeling flow-ecology responses to inform water management in a rapidly changing climate.
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Hutchins, M. G., B. Reynolds, B. Smith, G. N. Wiggans, and T. R. Lister. "Evaluation and interpretation of regional and site-specific hydrochemical data bases for water quality assessment." Hydrology and Earth System Sciences 3, no. 4 (December 31, 1999): 565–80. http://dx.doi.org/10.5194/hess-3-565-1999.
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Abstract. The spatial distribution of stream water composition, as determined by the Geochemical Baseline Survey of the Environment (G-BASE) conducted by the British Geological Survey (BGS) can be successfully related under baseflow conditions to bedrock geochemistry. Further consideration of results in conjunction with site-specific monitoring data enables factors controlling both spatial and temporal variability in major element composition to be highlighted and allows the value of the survey to be enhanced. Hence, chemical data (i) from streams located on Lower Silurian (Llandovery) bedrock at 1 km2 resolution collected as part of the G-BASE survey of Wales and the West Midlands and (ii) from catchment monitoring studies located in upland mid-Wales (conducted by Institute of Terrestrial Ecology), have been considered together as an example. Classification of the spatial survey data set in terms of potentially controlling factors was carried out so as to illustrate the level of explanation they could give in terms of observed spatial chemical variability. It was therefore hypothesised that on a geological lithostratigraphic series of limited geochemical contrast, altitude and land-use factors provide better explanation of this variability than others such as lithology at sampling site and stream order. At an individual site, temporal variability was also found to be of considerable significance and, at a monthly time-step, is explicable in terms of factors such as antecedent conditions and seasonality. Data suggest that the degree of this variability may show some relationship with stream order and land-use. Monitoring data from the region also reveal that relationships between stream chemistry and land-use may prove to be strong not only at base flow but also in storm flow conditions. In a wider context, predictions of the sensitivity of stream water to acidification based on classifications of soil and geology are successful on a regional scale. However, the study undertaken here has shown that use of such classification schemes on a catchment scale results in considerable uncertainty associated with prediction. Uncertainties are due to the large degree of variability in stream chemistry encountered both spatially within geological units and temporally at individual sampling sites.
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González, Raquel, Joan Vallès, and Teresa Garnatje. "Genome Size Variation Assessment in Vitis vinifera L. Landraces in Ibiza and Formentera (Balearic Islands)." Plants 11, no. 14 (July 21, 2022): 1892. http://dx.doi.org/10.3390/plants11141892.
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Plant genome size has many applications in different biological fields including ecology and plant breeding. The 2C value for Vitis vinifera L. has not been widely studied; furthermore, to date, no data from local landraces in the Pityusic Islands (the two smaller inhabited Balearic Islands, Ibiza, and Formentera) have been reported. This research aims to contribute to this knowledge and investigate whether there are variations between different grape landraces cultivated in Ibiza and Formentera and also among the same landraces on each island. To this end, 36 accessions of 15 cultivars and 6 landraces, identified with SSR markers, were assessed using flow cytometry. The results revealed that 2C values ranged from 1.09 pg to 1.28 pg. There were statistically significant differences in ‘AG1’ and ‘AG2’ landraces and ‘Santa Magdalena’, ‘Garnatxa’, ‘Danugue’, and ‘Valencí tinto/Grumier’ cultivars. No statistically significant differences were found in terms of the genome size content between islands. Statistically significant differences were found in accessions within ‘AG2’ landrace group and ‘Beba’ cultivar. The results presented here constitute the first-ever reported information on genome size in the genus Vitis vinifera in Pityusic, Balearic, and, in general, Spanish accessions, and they are one of the largest prospections in this field for this species anywhere. Further research should be conducted to explain the differences in nuclear DNA content found between landraces and cultivars studied here with others cultivated in different islands or countries to understand whether genome size varies in modern cultivars compared with local landraces. Additionally, it would be interesting to investigate whether there is a relationship between genome size and adaptations to diverse climatology conditions, crop management, and ripening characteristics.
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Hane, Y., S. Kimura, Y. Yokoyama, Y. Miyairi, T. Ushikubo, T. Ishimura, N. Ogawa, T. Aono, and K. Nishida. "Reconstruction of temperature experienced by Pacific bluefin tuna Thunnus orientalis larvae using SIMS and microvolume CF-IRMS otolith oxygen isotope analyses." Marine Ecology Progress Series 649 (September 10, 2020): 175–88. http://dx.doi.org/10.3354/meps13451.
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This study aimed to reconstruct temperatures experienced during the larval period by adult Pacific bluefin tuna Thunnus orientalis using high-resolution otolith stable oxygen isotope (δ18O) analysis. A novel otolith sample preparation protocol for secondary ion mass spectrometry (SIMS) analysis developed in this study reduced the background noise of SIMS measurements, enabling analyses of >10 times higher resolution around the otolith core compared to previous studies using conventional isotope ratio mass spectrometry (IRMS). The values obtained from SIMS were compared to those obtained by microvolume δ18Ootolith analysis using micromilling and conventional continuous-flow IRMS (CF-IRMS). There was a systematic offset (average 0.41‰ with SIMS resulting in lower values) most likely caused by matrix effects on SIMS δ18Ootolith values that can be calibrated using a strong linear relationship between SIMS and CF-IRMS measurements (r2 = 0.78, p < 0.001). The core-to-edge δ18Ootolith of 5 Pacific bluefin tuna revealed fine-scale seasonal variations in water temperature agreeing with known migration patterns. In addition, the ambient water temperature experienced during larval stages (about 10-20 d post hatch) estimated from otolith core δ18O ranged from 26.7 to 30.7°C, overlapping with temperatures associated with the occurrence of larval Pacific bluefin tuna. Combining SIMS and microvolume CF-IRMS δ18O otolith analyses offers a microscale examination of fish ecology that is not possible with conventional IRMS techniques. This novel method is particularly useful for understanding the early life history of fish that may be affected by climate change and reconstructing a well-resolved migration history for fish species that have small otoliths and/or narrow growth increments.
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Mulholland, M. R. "The fate of nitrogen fixed by diazotrophs in the ocean." Biogeosciences 4, no. 1 (January 12, 2007): 37–51. http://dx.doi.org/10.5194/bg-4-37-2007.
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Abstract. While we now know that N2 fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this N (and associated C), despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does N fixed during N2 fixation fuel autotrophic or heterotrophic growth and thus facilitate carbon (C) export from the euphotic zone, or does it contribute primarily to bacterial productivity and respiration in the euphotic zone? For Trichodesmium, the diazotroph we know the most about, the transfer of recently fixed N2 (and C) appears to be primarily through dissolved pools. The release of N varies among and within populations and as a result of the changing physiological state of cells and populations. The net result of trophic transfers appears to depend on the co-occurring organisms and the complexity of the colonizing community. In order to understand the impact of diazotrophy on carbon flow and export in marine systems, we need a better understanding of the trophic flow of elements in Trichodesmium-dominated communities and other diazotrophic communities under various defined physiological states. Nitrogen and carbon fixation rates themselves vary by orders of magnitude within and among studies of Trichodesmium, highlighting the difficulty in extrapolating global rates of N2 fixation from direct measurements. Because the stoichiometry of N2 and C fixation does not appear to be in balance with that of particles, and the relationship between C and N2 fixation rates is also variable, it is equally difficult to derive global rates of one from the other. This paper seeks to synthesize what is known about the fate of diazotrophic production in the environment. A better understanding of the physiology and physiological ecology of Trichodesmium and other marine diazotrophs is necessary to quantify and predict the effects of increased or decreased diazotrophy in the context of the carbon cycle and global change.
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Marston, Richard, and Robin Gray. "Spatial Distribution of Large Woody Debris on the Snake River, Grand Teton National Park." UW National Parks Service Research Station Annual Reports 23 (January 1, 1999): 119–23. http://dx.doi.org/10.13001/uwnpsrc.1999.3385.
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Large woody debris (LWD) plays a key role in controlling the ecology and geomorphology of streams. Woody debris traps coarse particulate organic matter and sediments (Andersen and Sedell, 1979; Bilby and Likens, 1980; Marston, 1982); provides habitat for aquatic insects (Angermeier and Karr, 1984; Benke et al., 1985); and provides cover in pools and slow water areas (Bisson et al., 1982, 1987; Tschaplinski and Hartman, 1983; Fausch and Northcote, 1992). The role of wood in affecting stream morphology is dependent on the size of the stream (Bilby and Ward, 1989). In smaller streams, woody debris can create step pool sequences (Heede, 1972, 1985; Marston, 1982), increase pool area (Murphy and Hall, 1981; Ralph et al., 1994), and reduce sediment transport (Bilby, 1984). Nakamura and Swanson (1993) noted that the importance of woody debris to the morphology of first order streams can be limited by the size of the debris, which is often large enough to bridge the channel and not interact with the flow. Woody debris plays a larger role when it enters the channel bottom, where it can divert flow and affect erosion and deposition. The scale issues raised by Bilby and Ward (1989) and Nakamura and Swanson (1993) are critical to understanding the role of woody debris. To date, LWD has not been adequately studied at watershed scales in larger rivers. In fact, there is little understanding of the relationship between LWD and the geomorphic pattern of the river channel (Piegay and Marston, 1998; Piegay and Gumell, 1997; Piegay, 1993). The purpose of this study is to document the distribution of LWD jams on the Snake River in Grand Teton National Park, Wyoming in order to understand the effects of LWD on channel morphology in large river systems.
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Chen, William, and Julian D. Olden. "Evaluating transferability of flow-ecology relationships across space, time and taxonomy." Freshwater Biology 63, no. 8 (October 16, 2017): 817–30. http://dx.doi.org/10.1111/fwb.13041.
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ZUPOLINI, LUCAS L., TATIANA MAGALHÃES, LEONARDO G. PILEGGI, and FERNANDO L. MANTELATTO. "Taxonomic revision of the speckled crabs, genus Arenaeus Dana, 1851 (Brachyura: Portunidae) based on morphological and molecular data." Zootaxa 4273, no. 3 (June 6, 2017): 362. http://dx.doi.org/10.11646/zootaxa.4273.3.3.
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The family Portunidae Rafinesque, 1815 presents a series of taxonomic problems such as paraphyletic groups, synonymizations, and unresolved complexes of cryptic species. Arenaeus Dana, 1851, encompasses only two species with mirrored distributions along the coasts of the Americas. Despite of comprising two widespread species, there is a scarcity of information on their biology and ecology and on the relationships with other genera in the family. Because of the lack of studies comprising both species and the imprecise or erroneous taxonomic descriptions for the species of Arenaeus, we conducted a thorough taxonomic revision of the genus and used data from fragments of the 16S rRNA and the cytochrome oxidase I (COI) genes to investigate the validity of Arenaeus cribrarius (Lamarck, 1818) and Arenaeus mexicanus (Gerstaecker, 1856). A range of easily discernible and objective characteristics distinguish the species, including the number of rostral teeth, the number of carpal spines, and the presence of a spine on the epistome region. This last feature, although never properly addressed in the literature, was diagnostic in discriminating the taxa. Results of molecular analyses also supported the separate identity of the two species. Assemblages generated in COI analyses reflected no geographic pattern or geographic partitioning, suggesting that dispersion and gene flow could be sufficiently high to hinder genetic differentiation through the extensive distribution range of the Atlantic species, A. cribrarius. Furthermore, molecular results and morphological analyses may indicate a closer relationship among particular groups of portunids and Arenaeus. Morphology of the carapace and of the first male gonopods may be the most prominent characteristics supporting such view. We have shed light on the status of the genus Arenaeus and its members, clarified some taxonomical issues, and provide an identification key for the species.